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Old 04-28-2020, 04:54 PM
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Originally Posted by D3MON View Post
is your flywheel keyed? or is it the collet type? if its the collet type really any SG type engine should fit, even something like the G3.0, (these were used on the later version of the RS4-3) or a long threaded crank engine. (short threaded wont work as there isnt enough threads to engage the pilot shaft/nut because of how thick the flywheel is.)
It uses a collet, so all good there.

engine mounts are probably going to be a pain to find, but doable.
I found a couple I think will work. The simplest are just a pair of spacers with longer screws. My chassis has a bunch of different spaced holes drilled around the engine mount area, so I believe just about any type of mount will fit.

and you are positive its not pinch that is causing the issue? i dont think i have ever heard of a sleeve/piston warping except for very extraneous circumstances, like overheating way past 300F. or mechanical failure.
if you pre-heat the engine to 200F with a heat gun, will it turn over then?
I'll try heating it up first, but should that be necessary just to get it to move? Before I tore it apart you could not pull the starting cord at all. Once I had the back of the engine off and could see the connecting rod, I could spin the shaft by hand the wrong way, pulling the rod down, but as soon as it got to the halfway point going back up the piston would bind up. Once I took the heatsink and plug off I could spin the shaft all the way around, but only because the sleeve could move up as well.

With the sleeve and piston removed and cleaned up, I can insert the piston from the bottom but it's very tight even there. When the top of the piston gets maybe a bit past the halfway point of the sleeve it's stuck fast. No way will it go anywhere near high enough to let the crankshaft turn a complete revolution when it's all assembled. No obvious damage to the sleeve or piston, and it was never abused. I only ran it maybe a dozen times, and none of that was racing. Just messing around in a parking lot, hardly any WOT to speak of.